This invention relates to polymerizable compositions and, more particularly, to compositions containing organic material having epoxide functionality and organic material having hydroxyl functionality.
Compositions based on the reaction of an organic material having epoxide functionality with an organic material containing hydroxyl functionality have previously been disclosed. For example, U.S. Pat. Nos. 2,914,490, 2,990,396, 3,242,104, 3,244,754, 3,281,491, 3,379,791 and 3,424,817 disclose such compositions containing one of a variety of acid catalysts or basic catalysts. These compositions are polymerized to thermoset resins by heating them at 50.degree. C. to 250.degree. C. from 1 to several hundred hours and accordingly they do not polymerize to a tack-free state in less than 30 minutes. Because of the need for use of thermal energy, and extended reaction times, in order to cure these compositions, they are not suitable or convenient for many applications.
U.S. Pat. Nos. 3,080,341, and 3,281,491 disclose compositions based on the reaction of an organic material having epoxide functionality with an organic material having hydroxyl functionality in the presence of a Lewis acid. Although such compositions polymerize to a tack-free state in less than about 15 minutes, the polymerization is inhibited by the presence of moisture. Consequently, erratic results can be obtained when curing the compositions under various conditions of humidity.
Furthermore, the rate of polymerization of epoxide-containing material with hydroxyl-containing material varies drastically with small changes in concentration of Lewis acid catalysts. Consequently, the rate of polymerization of such compositions can be difficult to control when using such catalysts. Also, Lewis acid catalysts may decompose with aging at elevated temperatures resulting in compositions whose cure times change significantly with time. This has been particularly noted with Lewis acid catalysts of the phosphorus family, e.g. PF.sub.5.
U.S. Pat. No. 2,897,163 discloses the polymerization of butadiene dioxide and a polyoxyalkylene polyol, in the presence of an alkali metal alcoholate, to polyhydric oxyhydrocarbon products. Such compositions require 2 to 20 hours at 90.degree. C. to 100.degree. C. to assure complete reaction and are therefore not rapidly polymerizable compositions.